It is estimated that 9.8 million Americans with a history of cancer were alive in 2001. American Cancer Society, Cancer Facts and Figures 2005, 1. Over one million new cases of cancer are expected to be diagnosed in the United States during 2005, and over 500,000 Americans are expected to die of cancer during that same year. Id. Consequently a great need exists for new drugs that can be used for the safe and effective treatment of cancer.